title: The effect of physical conditioning on antipyrine clearance.
abstract: The effects of physical conditioning on antipyrine clearance were studied in two groups of subjects. Healthy men not engaged in the systematic practice of any sport were compared with endurance runners (defined as men running > 80 km/week). Studies were carried out at three different periods of the annual plan training at 4-month intervals. Antipyrine was administered orally and pharmacokinetic parameters were obtained from saliva samples by the multiple-sample method. Endurance performance, expressed in terms of the maximal oxygen uptake (VO2max), the ventilatory threshold and the 4-mM x l(-1) lactate threshold (OBLA), was higher in trained than in control subjects at each of the three periods. Antipyrine clearance was also significantly elevated and antipyrine half-life reduced in runners during all periods. No significant difference in VO2max or antipyrine clearance was found between the various periods in either trained or control subjects. Both ventilatory threshold and OBLA increased significantly along the training period in conditioned subjects. Significant correlations were found between antipyrine clearance and VO2max, ventilatory threshold and OBLA. In summary, these results indicate an association between aerobic conditioning and increased hepatic oxidative metabolism of low-clearance drugs.
authors.affiliation: Institute of Physical Education, University of León, Spain.
authors.forename: J G
authors.initials: JG
authors.lastname: Villa
authors.forename: G
authors.initials: G
authors.lastname: Cuadrado
authors.forename: J E
authors.initials: JE
authors.lastname: Bayón
authors.forename: J
authors.initials: J
authors.lastname: González-Gallego
mesh_terms: D000328:Adult; D000983:Antipyrine / Q000032:analysis / Q000493:pharmacokinetics*; D001823:Body Composition; D015444:Exercise / Q000502:physiology*; D006339:Heart Rate; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D008657:Metabolic Clearance Rate; D010101:Oxygen Consumption; D010807:Physical Endurance / Q000502:physiology*; D012420:Running; D012463:Saliva / Q000737:chemistry
chemical_list: D019344:Lactic Acid; D000983:Antipyrine